Paragraph: When a metal rod M is dipped into an aqueous colourless concentrated solution of compound N , the solution turns light blue. Addition of aqueous NaCl to the blue solution gives a white precipitate O . Addition of aqueous NH ₃ dissolves O and gives an intense blue solution. Question: The metal rod M is

Step-by-step solution

Appearance of blue colour on addition of the metal rod M to the solution of N is an indication that metal may be Cu . Later formation of white precipitate on addition of NaCl and dissolution of this precipitate in aqueous ammonia confirm that while preipitate is of AgCl . This implies that the solution N is of AgNO ₃ . This confirm that the metal M is only Cu .